1. Field of the Invention
The present invention generally relates to computer graphics and, more specifically, to efficient round point rasterization.
2. Description of the Related Art
Round points are an important primitive needed in certain types of graphics rendering applications, such as in rendering particle effects. In many common scenarios, particle effects involve a large number of individual particles. Throughput in such scenarios is an important graphics system benchmark.
Current graphics systems typically render a given round point by rasterizing the point as a set of samples within a rectangular bounding region established around the round point. A graphics system may map the rectangular region onto a set of one or more tiles in screen space, each of which may be completely covered, partially covered, or not covered by the round point. Rasterization efficiency is reduced when empty tiles within the rectangular bounding region are processed by a graphics pipeline within the graphics system. A typical graphics pipeline is designed for relatively balanced throughput at each pipeline stage, and inefficiency at any pipeline stage may reduce overall performance. Therefore, inefficient rasterization of round points may result in an overall reduction in performance, leading to poor system benchmark results.
Accordingly, what is needed in the art is more effective technique for round point rasterization.